import java.util.Scanner;

/**
 * 牛客OR106
 */
// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            String a = in.next();
            String b = in.next();
            String ret = add(a, b);
            System.out.println(ret);
        }
    }

    public static String add(String a, String b) {
        StringBuilder stra = new StringBuilder(a);
        StringBuilder strb = new StringBuilder(b);
        StringBuilder sb = new StringBuilder();
        //将字符串逆置
        stra = stra.reverse();
        strb = strb.reverse();

        //统一长度
        int lena = stra.length();
        int lenb = strb.length();
        if (lena > lenb) {
            for (int i = 0; i < lena - lenb; i++) {
                strb.append("0");
            }
            lenb = lena;
        } else {
            for (int i = 0; i < lenb - lena; i++) {
                stra.append("0");
            }
            lena = lenb;
        }

        //遍历
        Boolean flag = false;
        for (int i = 0; i < lena; i++) {
            char cha = stra.charAt(i);
            char chb = strb.charAt(i);
            if (cha == '0' && chb == '0') {
                if (flag) {
                    sb.append('1');
                    flag = false;
                } else {
                    sb.append('0');
                }
            } else if ((cha == '0' && chb == '1') || (cha == '1' && chb == '0')) {
                if (flag) {
                    sb.append('0');
                    flag = true;
                } else {
                    sb.append('1');
                }
            } else {
                if(flag) {
                    sb.append('1');
                    flag = true;
                } else {
                    sb.append('0');
                    flag = true;
                }
            }

            if(i == lena-1 && flag) {
                sb.append('1');
            }
        }

        //将结果逆值回来
        sb.reverse();


        return sb.toString();
    }
}